Decoding 3D Geometry's Role in Earthquake Cycles: Application to the Central Chile subduction zone

Jorge G. Crempien, Marco Herrera, Marcos Moreno, & José Cembrano

Submitted September 10, 2023, SCEC Contribution #13176, 2023 SCEC Annual Meeting Poster #127

Earthquakes exhibit complex rupture patterns and variable sizes along fault segments. Understanding rupture segmentation and predicting large quake frequencies is vital for hazard assessment. This study focuses on the impact of plate interface geometry on interseismic coupling and coseismic ruptures. Employing 3D quasi-dynamic rate and state friction models, we investigate the dynamics of seismic cycles. Synthetic-parametric models reveal how dip and strike variations influence seismic barriers and rupture lengths. Through simulating diverse earthquake sequences, including a subduction zone scenario, we find that abrupt geometry changes impede earthquake propagation. These findings underscore fault geometry's role in seismic cycle segmentation. Our simulations within the Central Chile subduction zone spanning 5000 years confirm that abrupt geometry changes increase the likelihood of halting Mw8.0-9.0 earthquake propagation. These results align with historical seismic events and interface features, highlighting the significant role of fault geometry in seismic cycle segmentation.

Citation
Crempien, J. G., Herrera, M., Moreno, M., & Cembrano, J. (2023, 09). Decoding 3D Geometry's Role in Earthquake Cycles: Application to the Central Chile subduction zone. Poster Presentation at 2023 SCEC Annual Meeting.

Related Projects & Working Groups
Fault and Rupture Mechanics (FARM)